ATP-independent control of autotransporter virulence protein transport via the folding properties of the secreted protein. Journal Article uri icon



  • Autotransporter (AT) proteins are the largest class of extracellular virulence proteins secreted from Gram-negative bacteria. The mechanism by which AT proteins cross the bacterial outer membrane (OM), in the absence of ATP or another external energy source, is unknown. Here we demonstrate a linear correlation between localized regions of stability (ΔG(folding)) in the mature virulence protein (the AT "passenger") and OM secretion efficiency. Destabilizing the C-terminal β-helical domain of a passenger reduced secretion efficiency. In contrast, destabilizing the globular N-terminal domain of a passenger produced a linearly correlated increase in secretion efficiency. Thus, C-terminal passenger stability facilitates OM secretion, whereas N-terminal stability hinders it. The contributions of regional passenger stability to OM secretion demonstrate a crucial role for the passenger itself in directing its secretion, suggesting a novel type of ATP-independent, folding-driven transporter.

publication date

  • February 1, 2012

Full Author List

  • Renn JP; Junker M; Besingi RN; Braselmann E; Clark PL

Other Profiles

Additional Document Info

start page

  • 287

end page

  • 296


  • 19


  • 2